A team of researchers from the University of California have identified nine (9) big modifiable risk factors of Alzheimer’s disease. They’re responsible for two thirds of all Alzheimer’s case.
MD Jin-Tai Yu, PhD from the University of California San Francisco, and his colleagues conducted a meta-analysis of Asian patients and identified nine (9) modifiable risk factors of Alzheimer’s: carotid artery narrowing, obesity, type 2 diabetes, depression, low educational attainment, high blood pressure, high levels of homocysteine, frailty and current smoking.
The research team said that the population attributable risk for each of these individual risk factors ranged somewhere between 0.175 percent (0.175%) and 24.5 percent (24.5%). And when MD Yu and his colleagues combined all nine (9) of them in a single model, they saw that the population attributable risk rose up to 66 percent (66%).
The good news is that all nine (9) risk factors are potentially modifiable, which means that field experts may be able to come up with strategies that diminish the number of new Alzheimer’s cases.
It’s worth mentioning however that the new study was purely observational, so the root causes of Alzheimer’s disease are yet to be discovered. One former suspect was beta-amyloid deposition, but clinical trials failed to prove establish it as a true cause of the disease.
For the new study, MD Yu and his team examined 323 studies conducted between the years of 1968 and 2014, leading up to a total of 5000 patients and 93 potential risk factors.
Aside from the nine (9) risk factors, the research team also found grade I evidence of four (4) medical exposures which were proven to protect against Alzheimer’s disease – estrogen, statin, non-steroidal anti-inflammatory drugs and antihypertensives – and grade I evidence of four (4) dietary factors which were proven to protect against Alzheimer’s disease – coffee, folate, vitamin E and vitamin C.
And out of the nine (9) risk factors identified by the team, depression and high levels of homocysteine provided the strongest proof that they are without a doubt associated with an elevated risk of developing Alzheimer’s disease.
Second most likely group of factors to increase one’s risk of developing Alzheimer’s was the one including type 2 diabetes, carotid artery narrowing, high blood pressure and low blood pressure. However theses four (4) risk factors only applied to Asian patients.
The risk factors with the lowest chance of increase one’s chances of developing Alzheimer’s were cancer, heart disease, arthritis and metabolic syndrome.
MD Yu and his colleagues also found a group of risk factors that either increased one’s chances of developing Alzheimer’s or didn’t, depending on when exactly they occurred – having a high body mass index, having a low body mass index and low educational attainment during one’s mid-life years were linked to an increased risk of developing Alzheimer’s, however having a high body mass index during one’s later years was linked to a low risk of developing the disease.
Factors such as doing “brain exercises”, drinking lightly, drinking moderately and having stress later in life were also linked to a low risk of developing Alzheimer’s disease.
Current smoking was another low risk factor, however this finding only applies to Asian patients.
The new study was published recently, in the Journal of Neurology, Neurosurgery, & Psychiatry.
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